[John_AZ]

I do not think any posts to follow will offer encouragement. My guess is the cam belt was not fully seated in the crank pully.
What brand of belt did you use? Contitech is the preferred brand.

There is no valve cover and you could loosen the cam belt and put the cam to TDC mark. Then make sure #1 cylinder is at TDC by checking the crank pully marks, the flywheel mark on top of the bell housing and by using a stick in the #1 sparkplug hole and feel for piston at top of rotation. Be fery careful and if you feel resistance STOP. Try to get back to TDC with minimun cam and crank movement. Be very careful.

When you "tried to start and the engine backfired" and "now 80 degrees off" that usually causes valve damage to 2 valves.

Reset the timing and hand crank engine. Again, If you feel resistance, STOP.

If you have a leak down kit (Harbor Freight) you can test with out starting engine.

Best of Luck

John_AZ
1988 924S + 1987 924S